Guo Tongqing, Wang Xungang, Zhang Qian, Jia Yuna, Liu Hongjin, Hu Linyong, Zhao Na, Xu Shixiao, Duan Yingzhu, Jia Ke
Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, 810008, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
BMC Genomics. 2024 Dec 18;25(1):1194. doi: 10.1186/s12864-024-11093-5.
Meat quality in yak is influenced by the fluctuation of nutritional composition in different grazing seasons on the Qinghai-Tibetan Plateau. However, the molecular mechanism underlying in yak meat remains unknown. Therefore, this study aimed to investigate the seasonal dynamics of meat quality in yak by transcriptomics and metabolomics techniques. Twelve healthy female yaks with a similar weight were divided into two groups, including the warm season group (WS) and cold season group (CS). After slaughter, samples of longissimus lumborum were collected and subjected to transcriptomics and metabolomics to explore the effects of different seasons on meat quality.
Yak in the WS group had higher contents of n-3 Polyunsaturated fatty acid (PUFA), n-6 PUFA, threonine, and valine compared to the CS group, but the pH and b* values were lower. A total of 75 differentially expressed metabolites in the longissimus lumborum muscle were identified, with 23 metabolites upregulated and 52 metabolites downregulated in the WS group. These metabolites were mainly enriched in the pathway of glycine, serine and threonine metabolism, tryptophan metabolism, and carbohydrate digestion and absorption. In comparison, the WS group exhibited 262 upregulated genes in the longissimus lumborum muscle and 81 downregulated genes relatives to the CS group, which were enriched in the fat deposition of TGF-beta, ECM-receptor interaction, MAPK, and PPAR signaling pathway.
Among these, downregulated genes NPNT, GADL1, SESN3, and CPXM1 were associated with lipid metabolism and fat deposition in grazing yaks. It was found that DDC, DHTKD1, CCBL1, GCDH, and AOC1 involved in the tryptophan metabolism played an important role in the regulation of energy metabolism in yak.
青藏高原不同放牧季节营养成分的波动会影响牦牛肉品质。然而，牦牛肉品质形成的分子机制尚不清楚。因此，本研究旨在通过转录组学和代谢组学技术探究牦牛肉品质的季节性动态变化。选取12头体重相近的健康雌性牦牛，分为两组，即暖季组（WS）和冷季组（CS）。屠宰后，采集背最长肌样本进行转录组学和代谢组学分析，以探究不同季节对牦牛肉品质的影响。
与CS组相比，WS组牦牛的n-3多不饱和脂肪酸（PUFA）、n-6 PUFA、苏氨酸和缬氨酸含量更高，但pH值和b*值较低。共鉴定出背最长肌中75种差异表达代谢物，其中WS组有23种代谢物上调，52种代谢物下调。这些代谢物主要富集在甘氨酸、丝氨酸和苏氨酸代谢、色氨酸代谢以及碳水化合物消化与吸收途径。相比之下，与CS组相比，WS组背最长肌中有262个基因上调，81个基因下调，这些基因富集在TGF-β的脂肪沉积、ECM-受体相互作用、MAPK和PPAR信号通路中。
其中，下调基因NPNT、GADL1、SESN3和CPXM1与放牧牦牛的脂质代谢和脂肪沉积有关。发现参与色氨酸代谢的DDC、DHTKD1、CCBL1、GCDH和AOC1在牦牛能量代谢调控中起重要作用。
